A senior official at the European Medicines Agency (EMA) has said he believes there is a link between the AstraZeneca vaccine and extremely rare cases of blood clots reported in people who recently had the jab.
In an interview with Italy’s Il Messaggero newspaper, Marco Cavaleri, head of vaccines strategy at the EMA, said it was “clear there is a link with the vaccine” but there was still uncertainty about what exactly was causing such a reaction.
Mr Cavaleri said that among younger vaccinated people there was a higher than expected number of cases of cerebral thrombosis – blood clotting in the brain – compared with the general population.
A spokesperson for the EMA told The Independent the Pharmacovigilance Risk Assessment Committee (PRAC), which is reviewing the data, had “not yet reached a conclusion and the review is currently ongoing”, with an announcement expected on Wednesday or Thursday.
Europe’s regulator insisted as recently as last week that the “causal link with the vaccine is not proven” and continues to recommend people take the opportunity to get vaccinated when it is offered.
“EMA is of the view that the benefits of the AstraZeneca vaccine in preventing Covid-19, with its associated risk of hospitalisation and death, outweigh the risks of side effects,” the agency said in a statement released on 31 March.
Some countries have paused or restricted use of the vaccine to certain groups, including Germany, France and Canada.
The World Health Organisation has said the benefits outweigh the risks while AstraZeneca said in March its vaccine was 76 per cent effective in preventing symptomatic infections in a US trial, and that studies did not indicate higher risks of clotting.
Mr Cavaleri said the EMA’s evaluation of the AstraZeneca vaccine was “far from over” and that it was for individual countries to establish specific guidelines around which age groups were given which vaccines.
But he added: “In my opinion we can now say it, it is clear there is a link with the vaccine. What causes this reaction, however, we still do not know.
“These platelet-deficient cerebral thromboses appear to be the main event to investigate. In the next few hours we will say that the connection exists, but we still have to understand how this happens.”
Asked if the risk-benefit ratio was still in favour of the vaccine, he replied “yes”, but said the effects on different age groups needed to be examined “in more detail”.
He said: “Very meticulous work will be needed to understand if the risk-benefit ratio is in favour of the vaccine for all ages.”
Coronavirus-related deaths worldwide passed the 3 million mark on Tuesday, according to an assessment by the Reuters news agency.
Several European countries are experiencing a third wave of the virus, increasing the pressure on their already faltering vaccine programmes to scale up the rollout.
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